[单选题]
n airplane in straight level flight expx.mv mc: ,a0z b h:+*djrxpbo4e k-16vil-)cp*gubd 1 s; eq*esihjr;mriences a lift force $L$ that is proportional to the speed of the plane and is perpendicular to the axis of the wings and as shown in diagram.
On a banked turn at the same speed, the wings make an angle $θ$ with the horizontal.
Which of the following gives the centripetal force on the airplane?
